Method of refining urao.



l .above rnentioned is usually obtained in the move l In actual practice, while concentrating thevfinement, we concentrate thevsolution until.,

form of a hard crust one or more inches inV thickness, in which form it is removed from the vats by breaking into pieces which may' approximateaifoot square. The crude urao contains some very finefclay and more or less or anic matteigvand this is hard to ret'orn .the solution by simple filtration.

solution containing lthe urao in process of re- Vthe crystals of normal and acid carbonate 1 are formed while Athe solution is hot, but this is not necessary as we may. concentrate only to thepolnt Where 'the crystals will form v as soon as the admixture ci the solution cools a few degrees. In other words, We use our discretion Whether to Withdraw the solution when at a suiicient degree/of concentration to cause the crystals to separate While y.being Iconvcyed to the lter, or to separate it at a later stage while in or' upon the lter or drainin apparatus. eprefer to cause the precipi ation to take place ina' vessel as above descrlbed, but do not limit ourselves thereto. l 5 4 j Having thus described our invention, We

Patent: s .-1. The inethod herein described of treatclaim as'ne'w and desire to secure by Letters ingcrude urao which consists in breakin@ pieceswith a strong so ution essere fates of sodium, which consists in breaking Y A the'sanie into small pieces, removing insoluble" and organic' "matter, dissolving said pieces 1n Water to 'orm asolutiogi, evaporating by boiling -to a density allowing refined chlorids vand sulfate in the residua liquorf 8. The method herein, described, of treating crude urao, which lconsists in breakin the same intov small j'ieces, Washing sai pieces with a strong so ution of urao to mechanically remove therefrom insoluble and organic matter, dissolvingsaid pieces in hot fresh Water, clearing the solutionby settling, decantin and liltering, evaporating said solution by tion of heat thereto, so as to separate' carbonates of sodium from the hot mother liquid, drawing ofi' the chloride and sulfates of sodium and other impurities in `said mother liquor, and nally removing the pretio'n by boiling to form crystals of refined urao to precipitate, and drawin' ofi'Vv tlie boiling the same by the applicacip'tated crystals of sodium carb'onates and drying the same by centrifugal acmom ln testimony whereof We have signed our naines to this specification in the presence oi tivo subscribing Witnesses.

.Nor-ir trainata. ROBERT Gf. PADDOCK. -`Witnesses: .Y

P. JDEA, PHIL. S. l'vionrseun. 

